The present invention relates to a multi-piece solid golf ball. More particularly, it relates to a multi-piece solid golf ball having excellent flight performance and good shot feel at the time of hitting.
Many types of golf balls are commercially selling, but they are typically classified into solid golf balls such as two-piece golf balls, three-piece golf balls and thread wound golf balls. The solid golf balls generally occupy the greater part of the golf ball market, because they inherently have longer flight distance than the thread wound golf balls and have been improved to have soft and good shot feel at the time of hitting as good as the thread wound golf ball. The three-piece golf ball, when compared with the two-piece golf ball, has better shot feel while maintaining excellent flight performance, because the three-piece golf ball can vary in hardness distribution.
The three-piece solid golf balls are obtained by inserting an intermediate layer between the core and the cover layer constituting the two-piece solid golf ball and have been described in Japanese Patent Kokai Publication Nos. 244174/1992, 10357/1997, 10358/1997, 117532/97, 313643/1997 and Japanese Patent Nos. 257587 and 2658811. In these golf balls, it has been attempted to compromise the balance of flight performance and shot feel at the time of hitting by using thermoplastic resin, such as a block copolymer of amides, polyester thermoplastic elastomer, ionomer resin, polyolefin, for the intermediate layer, to adjust the hardness of the core, intermediate layer and cover and the hardness distribution thereof to a proper range.
However, the golf ball having sufficient performances has not been obtained in view of the balance of flight performance and shot feel. Therefore, it is required to provide a golf ball having longer flight distance and better shot feel.
A main object of the present invention is to provide a multi-piece solid golf ball having excellent flight performance and good shot feel at the time of hitting.
According to the present invention, the object described above has been accomplished by placing an intermediate layer between at least one layer of center and an outer layer to make a multi-piece solid golf ball, and adjusting a hardness and hardness distribution of the center, a hardness difference between the center and the intermediate layer and the hardness difference between the intermediate layer and the outer layer to specified ranges, thereby providing a multi-piece solid golf ball having excellent flight performance and good shot feel at the time of hitting.
This object as well as other objects and advantages of the present invention will become apparent to those skilled in the art from the following description with reference to the accompanying drawings.